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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>cosm</b> -   matrix cosine function</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>t=cosm(x)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>x</b>
        </tt>: real or complex square  matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>cosm(x)</b>
      </tt> is  the matrix cosine of the x matrix. 
    <tt>
        <b>t=0.5*(expm(%i*x)+expm(-%i*x))</b>
      </tt>.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

A=[1,2;3,4]
cosm(A)-0.5*(expm(%i*A)+expm(-%i*A))
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="cos.htm">
        <tt>
          <b>cos</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../linear/expm.htm">
        <tt>
          <b>expm</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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